Benchmark: foreach vs map by wayne

Tests:

foreach
let arr = Array(10000); arr.fill({name: 'ddd', age: 123}); const newArr1 = [] const newArr2 = [] arr.forEach((v) => { newArr1.push(v.name) newArr2.push(v.age) })
map
let arr = Array(10000); arr.fill({name: 'ddd', age: 123}); const newArr2 = [] const newArr1 = arr.map((v) => { newArr2.push(v.age) return v.name })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
foreach
map

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:133.0) Gecko/20100101 Firefox/133.0

Browser/OS: Firefox 133 on Linux

View result in a separate tab

Test name	Executions per second
foreach	5253.7 Ops/sec
map	4218.8 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the provided JSON data and explain what's being tested, compared, and some of the considerations involved.

**Benchmark Definition**

The provided benchmark is called "foreach vs map by wayne". It's a simple JavaScript microbenchmark that compares the performance of two approaches:

1. Using `forEach` loop to iterate over an array and push values into two separate arrays.
2. Using `map()` function to create a new array with transformed values.

**Script Preparation Code**

The script preparation code is empty, which means the benchmarker doesn't need to perform any initialization or setup before running the tests.

**Html Preparation Code**

Similarly, the HTML preparation code is also empty, indicating that no specific HTML structure needs to be generated for this benchmark.

**Individual Test Cases**

There are two test cases:

1. **foreach**: This test case uses a `forEach` loop to iterate over an array and push values into two separate arrays (`newArr1` and `newArr2`). The `forEach` callback function has access to the current value of each element in the original array, which is stored in the variable `v`.
2. **map**: This test case uses the `map()` function to create a new array with transformed values. The `map()` callback function returns the transformed value for each element in the original array.

**Test Results**

The latest benchmark result shows that the `map()` approach outperforms the `forEach` approach on this particular benchmark, with 2.25 times more executions per second (9161.1337890625 vs 4062.207275390625).

**Comparison Options**

Here's a brief summary of the options being compared:

* **forEach**: Iterates over an array using a traditional loop, pushing values into two separate arrays.
	+ Pros:
		- Easy to read and maintain for developers familiar with loops.
		- Can be used when working with legacy code or libraries that don't support `map()`.
	+ Cons:
		- Less efficient than `map()` due to the need to create intermediate arrays.
* **map**: Creates a new array with transformed values, using an iterator-like interface.
	+ Pros:
		- More concise and expressive than traditional loops.
		- Can be more efficient than `forEach` since it avoids creating intermediate arrays.
	+ Cons:
		- Less intuitive for developers unfamiliar with functional programming concepts.

**Library: Lodash (not explicitly used in this benchmark)**

While not explicitly mentioned, the use of `forEach()` and `map()` suggests that the developer is familiar with JavaScript's built-in array methods. If a library like Lodash were to be used in this benchmark, it might introduce additional overhead or alter the results.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntaxes being tested in this benchmark.

**Alternatives**

Some alternative approaches that could have been explored in this benchmark include:

* Using `filter()` to create a new array with filtered values.
* Using `reduce()` to accumulate values into an object.
* Using a custom iterator or generator function.
* Using a parallel processing approach, such as using Web Workers.

Keep in mind that the choice of approach depends on the specific requirements and constraints of the project.

Related benchmarks:

foreach vs map by wayne (version: 13)

Comparing performance of: foreach vs map

Created: 4 years ago by: Registered User

Jump to the latest result

foreach

map

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):